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UNSTRUCTURED Group-based health interventions are an important component of health promotion and management. To provide continuity of care throughout the COVID-19 pandemic, our institution undertook a rapid pivot to delivering group-based health interventions via a videoconferencing service which was securely embedded into both the electronic medical record and the patient portal to sustainably address immediate health service delivery needs during the pandemic and beyond. In this paper, we (1) describe the institutionally driven operationalization of a system to provide integrated synchronous video group visits across our hospital and (2) present a proposed strategy to comprehensively evaluate outcomes regarding their implementation, quality, and impact. Lessons for other institutions and the potential future role of synchronous video group visits to enhance how care can be scaled for delivery are discussed.

To serve as a reference point for future studies of the genus Cryptophasa Lewin, 1805, the type species, Cryptophasa irrorata Lewin, 1805, is redescribed with particular emphasis on the morphology of the male genitalia.

Cloud access security brokers (CASBs) operating in what has come to be called the cloud security gateway market are gaining industry acceptance as the next evolution in defending trusted zones for networked computing. The traditional clientserver framework of individual endpoint security coupled with enterprise network gateway security is proving inadequate to the overlapping extended networks created by mobility and cloud services. Useful measurement of the effectiveness of anti-malware and other cybersecurity defenses requires a clear definition of the trusted zones being defended. The value proposition of CASB services implies the successful defense of hundreds of individual trusted zones (one for each cloud service) for each individual user endpoint. The authors explore a different approach to defining the defended trusted zone in the era of multiple mobile endpoints and layered interacting cloud services. Defining the individual Office 365 user account as an example of a trusted zone for an individual user, the authors use traditional metrics of anti-malware efficacy to measure the properties of a well-defined singular trusted zone in the current environment where a user accesses hundreds of cloud services from multiple personal devices. Results of laboratory tests are presented where: the system-under-test is an individual Office 365 user account (Office 365 E3); the stimulus workloads (attack samples) are multiple forms of malicious activity (portable executable files, malicious links, weaponized documents, phishing emails); the attack vectors are through Office 365 cloud services (Exchange, SharePoint, OneDrive); and we measure the ability of malware to be successfully moved from being unavailable to the Office 365 user account to becoming available (regardless of what device the account owners use to access their individual Office 365 accounts). The goal of this research is to provide evidence as to the adequacy of adopting an individual user's overall internet access account as a simpler framework for the defended trusted zone for individual use of cloud services.

The aim of this study was to develop the linear haplotype sharing transmission disequilibrium test (LHS-TDT) method and combine this method with the simple regression method to estimate the precision of QTL positions in granddaughter designs. This precision was determined by Monte Carlo simulation in granddaughter designs. A single bi-allelic QTL at the midpoint of a linkage group and 26 markers with 1 cM intervals and with two alleles each were simulated. Three linear models, (i.e. the simple regression model, the linear haplotype sharing TDT method and the combination of these two models) were compared. The mean of absolute differences ( A ) between the estimated and true QTL position of each method was considered for six different scenarios consisting of combinations of a number of markers and the most frequent haplotypes. The mean of A , using the simple regression method, was 4.38 centimorgan (cM). The means of A using the LHS-TDT method were less than the simple regression method in all scenarios and ranged from 1.86 to 3.82 cM depending on the scenario. The mean of A using the combined method was more than the LHS-TDT method and less than the simple regression method. The means of A using the combined method ranged from 2.32 to 4.36 cM. Therefore, for populations similar to those population simulated in this study, the LHS-TDT was better than the simple regression method and the combined method for precision of estimated QTL position in granddaughter designs.

The Atlantic Salmon Broodstock Development Program is a partnership of researchers and producers that aims to breed salmon with an optimal combination of fast growth rate, low incidence of early sexual maturation, and good carcass quality for commercial aquaculture in Atlantic Canada. Estimation of genetic parameters for these traits is an essential step in the development of this breeding program. Four year classes of Atlantic salmon were produced, each consisting of 48–93 full-sib families. Marked fish from each of these families were randomly distributed to several producers to be raised under commercial conditions. At harvest, gutted body weights and sexual maturation level were observed in 812–3471 individuals per year class at processing plants. Additionally, colour score, astaxanthin, canthaxanthin, fat and moisture contents were recorded on 472 immature individuals from one year class. Genetic parameters were estimated with single- and multiple-trait animal models. Body weight, astaxanthin, canthaxanthin, colour, fat and moisture all exhibited moderate heritabilities (0.1–0.2), indicating that these traits should respond to selection. Positive genetic correlations were found between body weight and the carotenoid pigments, colour, and fat. These results indicate that direct selection for weight may have favourable indirect responses of higher colour scores and pigmentation but also an undesirable increase in flesh fat content. A properly weighted selection index should therefore be used to select broodstock for increased harvest weight and flesh colouration, while controlling flesh fat content.

(1) Genetic parameters for the sudden death syndrome (SDS) were estimated in meat-type chickens. Data were collected over 11 generations of selection for body weight within two distinct breeds (Cornish and White Rock). (2) The animal model was used exclusively with linear methods (LM) to estimate genetic parameters. Heritability (h2) of SDS on the liability scale was 0.30 +/- 0.002 and 0.25 +/- 0.002 in the Cornish and White Rock breeds, respectively. (3) A positive genetic correlation (r(g)) with ascites (AS) was determined (approximately 0.3 +/- 0.006). However, it was not possible to estimate the rg of SDS with body weight because of the low prevalence of the defect trait studied (1.8% in the Cornish and 1-5% in the White Rock). (4) Heritability of SDS calculated using male records only was 0.45 +/- 0.009 and 0.35 +/- 0.009, and r(g) with body weight was 0.30 +/- 0.010 and 0.27 +/- 0.009, in the Cornish and White Rock breeds, respectively. (5) In conclusion, the heart defect investigated was heritable with a positive genetic correlation with AS and body weight.

Female spawn date was investigated in three diverse strains of rainbow trout (Oncorhynchus mykiss) and two year classes of complete diallel crosses between them. Spawn dates at 3 and 4 years of age were recorded for individual females in two generations. Spawn dates were analysed to find the effects of strain and year of maturation, and to estimate repeatability. Strains had significantly different spawning seasons, and hybrids generally performed intermediate to pure strains, with little evidence of heterosis. Some differences in performance occurred between reciprocal crosses such that hybrids spawned more like the strain of their dams. Four-year-old maiden females spawned approximately 18 days later than 4-year-old repeat spawning females. Spawn date repeatability estimates were 0.72 and 0.83. The second spawning season occurred 6 to 35 days earlier than the first season, depending on strain. Spawning time appears to be inherited in an additive manner, so it should be possible to predict future spawning dates based on past data and change spawning time through selection.

Three White Leghorn strains, their two-way crosses, and two commercial lines were used to study the effects of aging on several parameters related to performance of fitness and nonfitness traits during the first laying cycle of hens housed three per cage. Egg number of the survivors (EPF) and egg number including mortality and morbidity (EPM) were divided into 12 periods of 28 d each, starting at age at sexual maturity. Egg weight (EW), specific gravity (SG), and albumen height (AH) were measured at 240, 350, and 450 d of age. Mean heterosis was significant over time, except for AH, increasing in magnitude with age for EPF, EPM, EW, and AH. Reciprocal effects were more important for egg quality than for egg production traits and were influenced by age. The age-related changes in additive, Z-chromosome, and heterotic effects varied among strains, showing that strains differ in their genetic schemes in response to aging. Nonadditive, environmental, and phenotypic variances increased with age for all traits. Additive variance increased with age for EPF, EW, and AH. Z-chromosome variance increased with age for EW and AH. Heritabilities decreased with age, except for EPF and AH. On average, genetic variance increased with advancing age. Improvement in lifetime performance may be obtained by selecting birds at older ages. As the relative increase with age in additive variance was larger for egg production than for egg quality traits, selection for the latter could be performed at early stages.

Genetic parameters for the ascites syndrome (AS) were estimated for meat-type chickens. Data had been collected over 11 generations of selection for body weight and other traits within two distinct breeds (Cornish and White Rock). Linear methods (LM) were used to estimate genetic parameters and also to analyze a binary measure of survival. Survival analyses (SA) were also conducted to estimate the effects of various factors influencing the incidence of AS by evaluating the number of days that the birds survived. The animal model was used exclusively with linear methods. Heritabilities (h2) on the liability scale were 0.12 +/- 0.02 and 0.22 +/- 0.01 in the White Rock and Cornish breeds, respectively; however, the genetic correlation (r(g)) with body weight was not possible to estimate due to the low prevalence of the defect trait studied (1.5% in the Cornish and 1.1% in the White Rock). Because males are more prone to AS, the h2 using the male records only were 0.22 +/- 0.017 and 0.41 +/- 0.009, and the r(g) were 0.35 +/- 0.007 and 0.22 +/- 0.009 in the dam and sire populations, respectively. In conclusion, the heart defect investigated was heritable and had a positive genetic correlation with body weight.

Inbreeding levels in three nucleus breeding populations of rainbow trout (Oncorhynchus mykiss) under selection for six generations were investigated. The inbreeding levels across generations as estimated from pedigree information (Pi) and effective population size (Ne) with the assumption of no selection and random mating, among the three populations were all at 11.3% or less. The levels of inbreeding estimated from Ne were generally lower than those calculated from Pi, except in the initial generations. The average rates of inbreeding (ΔF) calculated from Ne and Pi were 0.99% and 2.00%, respectively, for population 1; 0.90% and 0.53%, for population 2; and 0.72% and 1.38%, for population 3. These rates of inbreeding correspond to Ne of 50 and 25, for population 1; 55 and 94, for population 2; and 70 and 36, for population 3. These rates were within the acceptable range 2% to 0.2%, corresponding to Ne of 31 to 250 for avoiding loss of fitness as suggested by Meuwissen and Woolliams [Meuwissen, T.H.E., Woolliams, J.A., 1994. Effective sizes of livestock populations to prevent a decline in fitness. Theor. Appl. Genet. 89, 1019–1026.]. A large proportion of individuals had inbreeding coefficients (F) greater than zero across generations for each population but the individual F were generally below 12.5%. The occurrence of inbreeding can be detrimental to populations undergoing artificial selection. Therefore, the F levels reported here should be followed-up by a study on the impact of inbreeding on important performance traits in rainbow trout.

Three nucleus breeding populations of rainbow trout (Oncorhynchus mykiss) under selection for six generations were investigated for the effect of inbreeding on body weight at harvest. The coefficients of inbreeding for each individual were estimated from complete pedigree information starting at base generation zero. For each population within generation, inbreeding effect was estimated using a fixed linear model and a sire–dam mixed additive genetic model. Estimates of inbreeding effect per generation vary due to the different distributions of inbreeding coefficients in each generation. The magnitude of inbreeding effect for each population across generations were estimated using a fixed linear model and three sire–dam mixed models: additive (A), additive plus dominance (A+D), and additive plus dominance plus additive by additive epistasis (A+D+A×A) with the inbreeding coefficient, F as covariate. The estimates of inbreeding effect from the fixed linear model were substantially lower than those from the sire–dam mixed models for all populations. The models (A+D) and (A+D+A×A) exhibited quite similar estimates of inbreeding effect, which were substantially higher than the (A) model. The results suggest that addition of the additive by additive genetic effect in the (A+D) model does not have a significant outcome on the estimation of inbreeding effect because additive by additive genetic interaction may not be important for growth. For unbiased estimation of inbreeding effect, the (A+D) model with F as a covariate may be sufficient. The inbreeding effect on body weight at harvest calculated as the average of the estimates obtained from models A+D and A+D+A×A, were −1.6, −5.0, and –4.5% per 10% unit increase in inbreeding coefficients for populations 1, 2, and 3, respectively. These values meant body weight at harvest was moderately affected by inbreeding but were not high enough to cause any serious impact in the selective breeding program for rainbow trout in Norway. This implies that maintenance of moderate effective population size per generation and following a strict mating policy for breeders selected as parents for future generations could delay the accumulation of inbreeding and minimize its effect on growth.

Comparisons of growth for diploid and triploid full sibs from 20 families of Atlantic salmon (Salmo salar L.), ranging from 4 to 24 progeny/family, involved 628 individuals. Length and weight data, after approximately 75 weeks in seawater, indicated higher within and between family variances in triploids than in diploids. Regression analyses revealed that improvement of triploid populations might require measurements on triploid sibs of the diploid to be involved in reproduction.

Three White Leghorn strains, their two-way crosses, and two commercial lines were used to evaluate the effects of aging on mean heterosis, reciprocal, additive, Z-chromosome, and heterotic effects and their variances in two egg production traits during the first laying cycle. Egg number of the survivors (EPF) and egg number including mortality and morbidity (EPM) were evaluated from hens housed one per cage in a randomized block design. For analyses, egg number was divided into 12 periods of 28 d each. Synchronization of the records was achieved by starting recording at age at first egg. The mean heterosis was significant over time and increased with age for both traits (P

We report the case of a 55-year-old man who presented with a left hemisphere stroke. The initial computed tomography scan demonstrated a cerebral infarct in association with a left middle cerebral artery occlusion. Carotid duplex ultrasound imaging revealed a surgical grade stenosis of the proximal left internal carotid artery; however, in view of the uncertain benefits of internal carotid endarterectomy in the face of ipsilateral middle cerebral artery occlusion, surgery was deferred. Subsequent surveillance by transcranial Doppler imaging and repeat computed tomography demonstrated spontaneous recanalization. The patient proceeded to carotid endarterectomy with no complications.

Mental health services are in a state of flux. We struggle with the most basic concepts-can we distinguish between the need for "health" as opposed to "social" care? Mental distress is instantly recognizable, but less clear is what causes such distress or how we should respond to it. We have become so involved with current challenges that we assume that these are new-that we are living in a world beyond the end of psychiatric history. This article focuses on the Bethlem Hospital, 750 years old this year. An overview may help us to appreciate that our contemporary problems are the result of history and that the concept of care is a vital part of that. Nurses are trying to improve the response to the special needs of mothers with a mental illness. Such developments are the latest in a history of innovation and change. We too are part of that process and hopefully, our efforts will be seen as a meaningful contribution to the care of those with mental illness.

Twelve healthy subjects entered a double-blind placebo-controlled parallel group study to evaluate the tolerability of a 28 day course of twice daily dosage with Pulsincap TM capsules having the plug set for separation after 6 h. Eight subjects received Pulsincap TM capsules and four subjects received a matching placebo capsule. There was no active medication in any of the study capsules. Daily assessments were made of adverse events. Laboratory safety data (bloods and urine) and faecal occult blood were monitored weekly. Subjects returned for a post-study medical check during the fortnight following their final treatment session. All subjects completed their dosing schedule satisfactorily. Eleven adverse events were reported by six of the eight subjects in the Pulsincap TM capsule group and 14 adverse events were reported by the four subjects taking placebo. None of the adverse events in either group was considered to be causally related to treatment. Four males, but no females, had at least one positive test for faecal occult blood, two in the Pulsincap TM capsule group and two in the placebo group. In the single subject for whom the test was positive repeatedly, the occult blood was associated in time with an intercurrent dental problem and its treatment. Pulsincap TM capsules were well tolerated by the eight subjects who received them and there was no evidence of adverse events being causally related to this formulation. The results of this tolerability study support the further development of the Pulsincap TM formulation for delivery of active drugs.

Summary Inbreeding can lead to significant depression of growth and other important traits in fish. Computer simulation was used to compare two mating systems in a fish population, for a trait controlled by different number of loci and different levels of dominance. The choice of a suitable mating system is one way of avoiding inbreeding. A fish population was modelled, in which the simulated traits were controlled by a different number (75 and 150) of unlinked loci, each with equal gene effects. The initial gene frequencies were 0.5 for the two alleles. The dominance was either complete or partial. Parents for the next generation were selected on individual phenotypic performance. Selection was carried out over five generations in a population of 2000 offspring. For each generation, 0.5% of the individuals were selected and mated, according to either a single-pair mating system or a factorial mating system. The factorial mating system produced a higher genetic response and lower inbreeding depression for all traits, compared with single-pair mating, with the difference being most pronounced for traits with complete dominance and controlled by a large number of loci. Zusammenfassung Paarungssystemvergleich in einer Fischpopulation–Eine Simulationsuntersuchung Computersimulierung wurde verwendet, um zwei Paarungssysteme in einer Fischpopulation zu vergleichen. Das simulierte Merkmal wurde von unterschiedlich vielen Loci beeinflusst und auch Dominanz nahm Werte verschiedener Hohe an. Inzucht kann zu signifikanter Depression des Wachstums und auch anderer wichtiger Merkmale fuhren. Die Wahl eines geeigneten Paarungssystem kann aber dazu beitragen, Inzucht zu vermeiden. Es wurde eine Fischpopulation, in der das simulierte Merkmal von unterschiedlich vielen nicht gekoppelten Loci (75 oder 150), mit den selben Geneffekten, beeinflusst wurde, erstellt mit anfanglichen Genfrequenzen viz 0.5. Die Dominanzeffekte entsprachen entweder der Halfte oder dem ganzen additiven Geneffekt. Die Elterntiere der folgende Generation wurden auf ihre individuelle phanotypische Leistung wurde uber 5 Generationen selektiert, und aus jeder Generation 0,5% der 2000 Nachkommen genommen. Die selektierten weiblichen Individen wurden entweder mit einem oder mit samtlichen mannlichen Individen angepaart. Die Anpaarungen mit den gesamten mannlichen Individen erzielten, fur samtliche Merkmale, den hochsten genetischen Fortschritt. Der Unterschied war besonders auffallig fur Mermale mit vollstandiger Dominanz, die gleichzeitig auch von einen grorsen Anzahl von Loci beeinflusst wurden.

Staffat a south east London NHS trust are discovering how dance can improve their communication with patients with learning disabilities. Weekly dance sessions, run by Magpie Dance, are now also being made available to people with dementia, autism and other conditions. Through dance people can express emotion, build confidence and change their lives.

A nurse has set up an innovative therapeutic project in Norfolk to help people with mental health problems improve their physical fitness and re-engage with the outside world. Participants in the countryside walks have lost weight, made friends, and rediscovered their enjoyment of the outdoors.

Feed consumption and feed efficiency data obtained over nine generations from three selected strains of broilers were adjusted for differences in either initial or initial and final test BW (at 28 and 42 d, respectively). Genetic and environmental variables were estimated for each strain using an animal model with restricted maximum likelihood procedures to avoid bias due to reduced genetic variation caused by selection. Variance component and heritability estimates before and after adjustment of these traits for differences in test weights were evaluated. Adjustments of feed consumption data for either initial test BW or both initial and final test BW reduced additive genetic and environmental variation. Reductions were relatively greater for additive genetic than for environmental variance, thereby reducing the heritability of the adjusted trait. Adjustment of feed efficiency for initial test BW altered additive genetic variation little and reduced environmental variation slightly; however, correction for both test BW reduced variation of both components. Heritability of adjusted feed efficiency was 40% larger (.33 to .35 vs .21 to .28) than for uncorrected feed efficiency, but phenotypic variation of the adjusted feed efficiency was reduced 42% (5.82 to 6.13 vs 10.30 to 11.35). Heritabilities of feed consumption and efficiency were essentially the same (.34 and .36) after adjustment for both test weights. Changes in genetic and environmental variation and heritability due to adjustments were similar for the three strains.

Commercial poultry breeders need to select for a wide array of traits, and conventionally they are included in a selection index. There are problems in determining economic weights and the assumptions of additivity for fertility and hatchability. The approach taken for the long-term multiple trait selection study reported here was to maintain the original high levels of these traits by culling potential breeding males and females on the basis of their parent family records. Only the lowest 10% of families were culled with no positive selection among the remaining families. As a result, selection differentials were low and averaged .40% for fertility and 1.14% for hatchability for the six selected strains. This maintained high fertility and hatchability levels over the whole study, so that the regressions for fertility and hatchability (as deviations from controls) were nonsignificant except for a small, significant increase in fertility over the last 10 yr. Mean inbreeding levels at the end of the study varied between 21.8 and 26.2% for the four strains selected for 29 or 30 yr and from 9.9 to 11.6% for the two strains selected for 11 generations. There was no evidence that inbreeding depression affected selection because breeding males and females selected each generation were as inbred as the average bird in each strain. The culling procedure used was effective in maintaining the two reproductive traits so that most of the selection pressure could be applied to the other economic traits.

Uneyed-egg, eyed-egg and alevin mortalities were compared for 750 diploid families of brook trout ( Salvelinus fontinalis ), brown trout ( Salmo trutta ) and their reciprocal hybrids, known as tiger trout, produced over 4 years. The reciprocal tiger trout crosses experienced higher overall mortality than either pure species. The brook female × brown male cross experienced high mortality at all three stages examined, while the reciprocal cross experienced heavy losses only at the alevin stage, resulting in higher overall survival rates. Within the brook female × brown male cross, females were the most important source of variation for all types of mortality, but brown males were also an important source of variation for uneyed-egg mortality. In the reciprocal cross, male and female parents were both important sources of variation for alevin mortality, the major source of early mortality in this cross. For brook trout female parents, hybrid offspring mortality was not significantly correlated with mortality among pure brook trout offspring. Similarly, mortality of hybrid offspring of brown trout dams was not correlated with mortality of brown trout offspring except at the eyed-egg stage, a rather unimportant source of mortality in this cross. The influence of triploid induction on survival rates among brook trout and tiger trout families was studied by comparing diploid and triploid full sibs over 87 pairs of families. In general, triploid induction improved the survival rates of tiger trout at the alevin stage, but reduced survival at the uneyed-egg stage, so that overall survival was not greatly improved. Thus, early survival of tiger trout can be maximized by the use of the brown female × brook male cross, and by selection of the females and the brook males based on the survival rates among their hybrid offspring. The usefulness of triploid induction in the production of tiger trout will depend on modification of the induction techniques so that mortality from the induction is minimized.

Data from five generations of selected and control strains of a pedigreed synthetic broiler dam population were analyzed to estimate heritabilities for production traits. The population was composed of one selected strain with two replicates and one control strain in each generation. Eight production traits were measured. Growth rate traits included body weights at 28 (BW28) and 42 days (BW42) and weight gain (WG) during Days 28 to 42. Feed traits included feed consumption (FC) and feed efficiency (FE) during 28 to 42 days. Carcass traits included carcass weight (CWT), abdominal fat weight (AFW), and abdominal fat percentage (AFP) of carcass weight at 47 days. Realized heritability estimates for the two selected traits, BW28 and FE, were .32 and .14, respectively. Heritability estimates based on sire variance components were .38 for BW28, .41 for BW42, .30 for WG, .35 for FC,. 16 for FE, .43 for CWT, .53 for AFW, and .53 for AFP. Heritability estimates for feed traits adjusted for BW28 and BW42 as covariates and AFW and AFP adjusted for 47-day CWT as a covariate were averaged after weighting. Heritabilities for adjusted FC, FE, AFW, and AFP were .27, .26, .48, and .49, respectively. When either FC or FE and either BW or WG are both being selected, the feed traits should be corrected for differences in growth rate during test. The need for adjustment is evident from the differences in heritability estimates for feed traits before and after correction for growth differences as well as the absence of correlation between adjusted feed traits and growth rate.

Genetic improvement in production of commercial layers was examined by comparing production profiles of three strains representing commercial stocks of the two decades between 1950 and 1970, and by...

In the future, quantitative techniques will probably be used in industry as part of Tier II studies for the evaluation of chemicals and drugs for their neurotoxic potential. Movement towards quantifying some structures or neuropathological changes will be made possible by advances in tissue preparation and computer technology. Emphasis will need to be placed on standardized techniques, good quality samples and sampling techniques in order to produce good quantitative data in a reasonable time. In this paper, different sampling techniques are evaluated using a cross section of rat sural nerve as the tissue for quantitative investigation.

A major challenge of any knowledge management system is to meet the varied needs of diverse constituencies, both internal and external. Comprehensive, integrated systems are costly to develop, may take considerable time to implement and often lack adaptability. For technical knowledge management related to bit development and application, ReedHycalog has avoided these limitations by employing a range of modules that meet specific needs. The comparatively narrow focus of each of these applications minimises development and maintenance costs, allows rapid introduction, and permits quick adaptation to changing needs. Integration of these diverse packages is achieved through a common software interface and established company practices, supported through user training. This paper explores the character of ReedHycalog's principle knowledge management modules; we consider how the systems position the company to be better able to create lessons learned, and to establish best practices; we demonstrate the adaptability of the approach in the rapid introduction of a product development monitoring system; we examine, as an example of routine engineer usage, how the user interfaces with each module to produce a technically sound client product proposal. Such an approach, using the best solutions for specific needs, yet integrated through a designed culture of accessibility and training, delivers a low cost, flexible knowledge management system. This discrete modular solution is a viable and effective alternative to a fully integrated knowledge management system.

Aquatic total phosphorus (Tot-P) is measured at fish-cages in Lake Huron for environmental regulatory compliance. An improved understanding of how Tot-P is manifested in the near-field (

The objective of the current study was to compare the changes in a fitness trait when selection is performed for 5, 10, and 20 generations on a production trait that influenced its expression. Responses to single-trait selection for growth based on phenotype or animal model predictions were compared by computer simulation. Two-trait index selection was performed when a trait, related to the fitness trait, was included in the index with the production trait. The phenotypic expression of the fitness trait among the sibs was also considered as a selection factor for single-trait and two-trait index selection. For a fixed increase in the expression of the fitness trait, mass selection produced a larger increase in the production trait than did use of standard animal model best linear unbiased prediction under single-trait selection. The reduction in the genotypic mean of the fitness trait was accompanied by an increase in its phenotypic expression. The use of sib information and an indicator trait reduced the level of expression reached by the fitness trait.

1. Fertility and hatchability of 3 White Leghorn strains and their 2-way crosses were examined in the 1st laying cycle to evaluate the effects of ageing on mean heterosis, reciprocal effects, additive (A), Z-chromosomne (Z) and heterotic effects (H), as well as on their variances. 2. Fertility and hatchability were evaluated at 37, 47 and 70 weeks of age for hens housed 1 per cage in a randomised block design. The mean heterosis was significant over time and increased with advancing age for both traits. Reciprocal effects were not significant across periods and did not show a consistent trend with age. 3. The pattern of age changes in A, Z and H effects varied among strains, indicating genotypic differences in response to ageing. The additive, heterotic, environmental and phenotypic variances increased at the end of the cycle for both traits, except for the additive variance of hatchability, which increased until 47 weeks of age but declined thereafter. 4. Heritability increased with age for fertility but did not show a consistent pattern across the cycle for hatchability. Genetic variance for fertility and hatchability increased at the end of the cycle, stggesting that improvement in performance during the 1st production cycle of layers could be achieved by selecting animals at older ages.

He might have celebrated his ninetieth birthday in April, but Thomas Szasz’s ability to pull a crowd while refusing to pull his punches remains undimmed. Ian McMillan reports